Remove poppler-gi instruction

The dependency appears in the AUR recipe now.

Author: Cimbali

README.md

@@ -45,14 +45,12 @@ Here is what the 2 screen setup looks like, with a big notes slide next to 2 sma
   git clone https://aur.archlinux.org/python-pympress.git
   cd python-pympress
   makepkg -si
-  pacman -S poppler-glib  # dependency temporarily missing from AUR package
   ```
 
   Or using any other tool to manage AUR packages (yay, pacaur, etc.):
 
   ```sh
   yay -S python-pympress
-  pacman -S poppler-glib  # dependency temporarily missing from AUR package
   ```
 
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